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    <script>
        // typeof 1--返回的是一个字符串，这个字符串描述了(同一个单词) 变量的类型
        console.log(typeof 1);//--> number这个字符串
        console.log(typeof typeof 1);
        console.log(typeof 'number');//string

        console.log(typeof typeof {});

    </script>

</body>

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